When New Orleans plays the Jets on Sunday at MetLife Stadium in East Rutherford, N.J., it won't be the first time Saints defensive coordinator Rob Ryan and his fraternal twin, Jets Coach Rex Ryan, have found themselves standing on opposing NFL sidelines.
But it doesn't make the matchup any less intriguing.
The dynamic is different than the usual connections – opposing coaches who have worked together, players lining up against former teams. Blood is thicker than that, and the bond between twins is tighter still.
"I think we're pretty similar in our spare time, whether it's jokesters or whatever," Rob said Friday. "We're fortunate to have a great relationship, as tight as brothers can be. Off the field we're best of friends."
"Our personalities, even the way we sound and everything else (are similar)," Rex said. "They say we are fraternal twins, (but) I'm not sure about that. He's his own man.
"He's his own man (and) he is going to play his defense the way he sees it. I'm going to do the same thing, but don't kid yourself, we will copy things from each other. We talk all the time and stuff. I know one thing, I think we probably have respect to the league as being pretty decent on defense, both of us."
Undeniably, Rob has been a boost for the Saints.
Last season New Orleans surrendered a league-record 7,042 yards, 440.1 per game. This year the average is down more than 100 yards per game, to 332.4, and the Saints (6-1) are one victory shy of tying last season's total as they prepare to take on the Jets (4-4).
Rob Ryan has re-instilled the kind of confidence and swagger in the Saints defense that oozed from his father, former NFL coach and defensive guru Buddy Ryan, and landed on him and Rex.
"I think you could see that," Saints Coach Sean Payton said. "The thing that I had heard in the process of interviewing him was that the relationship, not only with his players but with his staff, was very positive. So that was something you could see."
So it was no surprise that Rob didn't shy away from the chance to join Payton's staff. He has been defensive coordinator in Dallas (2011-12), Cleveland (2009-10) and Oakland (2004-08).
"It was such a blessing to get a chance to come here," he said. "It's a big deal. It is. When you go to an organization like this, it's like winning the lottery. I was fortunate enough to do it."
"I know one thing, he's not afraid of a challenge," Rex said. "He loves the fact that Sean Payton was the head coach and the guys he would be around on the other side of the ball. I know he was excited to have (assistant head coach/linebackers) Joe Vitt coaching with him.
"Certainly a Ryan is not afraid of a challenge so he just jumped right in. The one thing about it to me, this team should be undefeated but they let one game get away. Really, New England? (But) what a job they have done, and arguably the best team in the league right now."
The New England reference? A playful jab, and the brothers aren't short on them. Likely, several have been exchanged this week. They won't be changed by this week's opponent, especially since it's not the first time (Rex's teams are 4-0 against Rob's).
"When we first played in college it was pretty cool," Rob said. "Now it's just, honestly, when the ball is snapped, it's nameless, faceless opponent until you go shake his hand across the field.
"We usually have good times with it, (but) right now it's just too important. Our season is too important to have any distraction, I'm sure it is for him, too."
"It will shut down because of a game like this, but we will get a jab or two at each other," Rex said. "Now, it is all about business. Obviously, we need a win and they need a win and that's really what it is about.
"It's about our teams (more) than it is us. I think that's where we want the focus to be. With that being said, I'm sure there will be a playful jab every now and then."
Mostly, though, Sunday will be about work, and two brothers whose teams want to win as much as they do.
"He's got a job to do and that's great," Rob said. "But more important, I've got a job to do. I want to do it well. That's what I was hired to do."
"We are going to try and beat each other's brains in and you want to have your hand raised in victory at the end of the game," Rex said. "That is the most important thing.
"You hate it, because you pull for each other so bad. Every single week I don't care, during the game I'll be on the sidelines and they will be flashing (other) scores, (and) I'll be looking at one game. I want to see how he is doing. I want him to be doing great.
"But when you play against him it's like you go from one extreme to the other. We have to win. You don't really care that that is your brother over there and then after the game it is just whatever happens, happens. (But) certainly you want to be on the winning side of it, for sure."